These levers are sturdy but not too big, and they make mounting even the most troublesome tire/rim combo a breeze.
The real magic comes from that weird pointy end. You jam the pointy hook up into the tight space under the bead of a tire. The little catch keeps the lever from slipping out while you lever the tire bead up over the lip of the rim. The big bead-catch keeps the bead from sliding down the lever the wrong way when you try to lever it up onto the rim.